Antiperspirant and/or deodorant compositions are generally applied to an axillary region to limit perspiration and/or to limit or kill bacteria in this region. In this way, body odor caused by bacterial growth is limited or at least reduced.
Antiperspirants and/or deodorants can be delivered topically in solid or soft solid form using, for example, a stick applicator.
‘Alum’ represents a class of naturally occurring chemical compounds typically having the formula AM(SO4)2·xH2O, where A is a monovalent cation such as potassium, sodium or ammonium, and M is a trivalent metal ion such as aluminum and x is typically 12. Alum is known to have deodorant, astringent and antiperspirant activity, and therefore, it is often used in antiperspirant/deodorant compositions.
Typically during the manufacture of a solid or soft solid antiperspirant/deodorant composition, the ingredients of the composition are combined and heated to melt the components, and the melted components are mixed. After mixing, the molten composition may be poured directly into dispensers, where it is allowed to cool and harden. The dispersers are then capped to preserve the solid compositions until use.
However, when alum is present in the solid or soft solid antiperspirant/deodorant compositions, it has a tendency to settle at the bottom of the dispenser before the compositions harden into a solid. This leads to an uneven distribution of alum through the solid or soft solid form, with an increased amount of alum at one end of the form as compared to the other end.
Clay materials such as bentonite and hectorite are often used as suspending, agents in antiperspirant/deodorant compositions. However, these materials are expensive.
Therefore, there is the need to provide improved, cost-effective antiperspirant/deodorant compositions comprising alum which resist settling of the alum.